Perhaps the only piece of musical theatre ever set in the primordial goo, Yeast Nation: The Triumph of Life follows a group of single-celled yeasts dwelling at the bottom of the ocean billions of years ago. The show is half Shakespearean tragedy, half Broadway musical, with a healthy dose of irreverent humor. Created by Tony Award-winners Greg Kotis and Mark Hollmann (Urinetown), the musical is running at San Francisco’s Victoria Theatre from Oct. 3 to Nov. 1.